AssetTrackerRK 0.3.1 with AssistNow support

[UMD]

Just referencing the v1.5.0-rc.1 compile target with DeviceOS v1.5.0-rc.1 issue here for completeness (which @peekay123 has already posted to) :

Updating from DeviceOS 1.4.4 to 1.5.0-rc.1 -> SOS Panic 1

@avtolstoy, Have updated an existing production P1 device from DeviceOS 1.4.4 to the just released 1.5.0.rc-1 by simply compiling against 1.5.0-rc.1 and OTA downloading in the usual way. The outcome is SOS 1 blink - HARD FAULT, which comes up immediately upon reset. As I could enter safe mode, I recompiled targeting v1.4.4 and was able to download ok. My program then successfully ran (good), but it was reporting back as running 1.5.0-rc.1. Next I recompiled targetting v1.5.0-rc.1 and OTA do…